1. Field of the Invention
The present invention relates to a charge-and-discharge management system which controls the charge and discharge between vehicles and the vehicles exterior. More specifically, the present invention relates to a charge-and-discharge connector which allows the transfer of electric power between vehicles and a charge-and-discharge control device outside the vehicles, and to a vehicle which can transfer electric power from and to the charge-and-discharge control device outside the vehicle through the charge-and-discharge connector.
2. Description of the Related Art
Electric vehicles carry an electric storage device (for example, a rechargeable battery, a capacitor, etc.) and run using the driving force generated from a power plant (for example, motor etc.) driven with the electric power stored in the electric storage device. As such electric vehicles, for example, an electric vehicle (EV), a hybrid vehicle (HV), etc. are included.
In such electric vehicles, the technology for charging the electric storage device carried in electric vehicles by the electric power supplied from external power supplies, such as commercial power supplied to each home (for example, source of supply of the comparatively low voltage of 100V or 200V grade), has been already developed. Hereinafter, vehicles which can charge the electric storage device (for example, battery etc.) carried in vehicles by the external power supply may be referred to as a “plug-in vehicle.”
In addition, in hybrid vehicles (HVs), although the electric storage device carried in HV can be charged by driving a motor, which usually functions as a power generator, as the source of power, for example, by an internal-combustion engine or a regenerating brake etc. carried in HV, the electric storage device can be also charged by an external power supply as mentioned above. Such HV may be referred to as a plug-in hybrid vehicle (PHV).
In the art, as the standard of the electric vehicle which can charge an in-vehicle battery from a residence, “SAE Electric Vehicle Conductive Charge Coupler” (Non-Patent Literature 1) is enacted by SAE (Society of Automotive Engineers) in the United States of America, and “General Requirements for Conductive Charge System for Electric Vehicles” (Non-Patent Literature 2) is enacted also in Japan.
Moreover, in the Non-Patent Literature 1 and Non-Patent Literature 2, the standard about a control pilot (CPLT) is defined. The control pilot is defined as a control line which connects the control circuit of EVSE (Electric Vehicle Supply Equipment) supplying electric power from yard (in-plant) wiring to vehicles with the grounded part of vehicles through the control circuit on the side of vehicles and, based on the CPLT signal (pilot signal) which is communicated through the control line, the connection state of a charge cable, the propriety of the electric power supply from power supply to vehicles, and the amperage rating of EVSE, etc. are judged.
On the other hand, it has been proposed to supply electric power to external equipment (for example, a power supply, electric load, etc.) for electric power to be supplied from the electric storage device carried in electric vehicles as described above for the purpose of effective use of electric power from a viewpoint of environmental protection, etc., and relief of electric power shortage in the time of disaster etc. In other words, it has been proposed to use the electric storage devices carried in electric vehicles as electric supply equipment to external equipment for electric power to be supplied.
In this case, it is also possible to constitute the electric supply mechanism for supplying electric power to external equipment for electric power to be supplied from the electric storage device carried in electric vehicles separately from the charge mechanism for supplying electric power to the electric storage device carried in electric vehicles from external electric supply equipment (for example, commercial power etc.) to charge the electric storage device. However, establishing an electric supply mechanism separately from a charge mechanism in such a way may cause various problems, such as enlargement of vehicles, complication of electric supply/charge mechanism, increase in the manufacturing cost of vehicles, etc.
Then, various technologies, which make it possible to change between and perform the electric supply to external equipment for electric power to be supplied from vehicles and charge to the electric storage device carried in vehicles from external electric supply equipment in one mechanism, has been proposed in the art.
For example, the technology in which, by the energy management system (EMS: Energy Management System) which makes the power transmission possible mutually between the battery of an electric vehicle and a residence, it is judged whether the main controller on the side of the residence should be set in charge mode or discharge mode, a charge-and-discharge control signal is transmitted to the battery controller on the side of vehicles through a communications aerial (antenna) from the charge-and-discharge controller on the side of the residence, and based on the charge-and-discharge control signal received through the communications aerial, charge control or discharge control is performed on vehicles has been proposed (refer to Patent Document 1). However, forming a communications aerial separately in such a way causes increase in the manufacturing cost of the system, and complication of a control device.
Moreover, it is also possible to prepare the connector and inlet used on the charge to the electric storage device carried in vehicles from external electric supply equipment, separately from the connector and outlet used on the electric supply to external equipment for electric power to be supplied from vehicles, or to integrate the inlet and outlet carried in vehicles and preparing separately the connector for charge and the connector for electric supply to change between and perform the electric supply to external equipment for electric power to be supplied from vehicles and the charge to the electric storage device carried in vehicles from external electric supply equipment. However, even in such configurations, there is a possibility of causing problems, such as complication of a charge-and-discharge system and increase in a manufacturing cost, and misuse of a connector, etc.
Then, in the charge-and-discharge system of the vehicles which can charge the electric storage device carried in vehicles from the power supply outside the vehicles, and can supply electric power from the electric storage device to the power supply outside the vehicles or the electric load outside the vehicles, the technology in which the control signal (CPLT signal) for distinguishing whether an electric power cable is for charge or for electric supply is generated in the signal generation circuit that the charge-and-discharge system includes and, in accordance with the control signal provided from the signal generation circuit, the control device carried in vehicles controls a power converter by any in charge mode and electric supply mode has been proposed (refer to Patent Document 2).
However, in order to judge whether it is charge mode or electric supply mode based on a CPLT signal as mentioned above, a signal generation circuit must be able to generate a CPLT signal in both of charge mode and electric supply mode. On the other side, since a CPLT signal cannot be normally generated in the situation where the charge-and-discharge control device cannot operate normally due to, for example, the power failure in the time of a disaster, etc. or failure of a charge-and-discharge control device, etc., especially in such cases, it is desired to supply electric power to the power supply outside the vehicles or the electric load outside the vehicles from the electric storage device carried in vehicles. Nevertheless, in such cases, the electric storage device carried in vehicles cannot be charged by the power supply outside the vehicles, and electric power cannot be supplied to the power supply outside the vehicles or the electric load outside the vehicles from the electric storage device carried in the vehicles, either.
As mentioned above, in the art, there has been a continuous demand for a technology which makes it possible to transfer of electric power mutually between vehicles and the vehicles exterior under control by a charge-and-discharge management system at normal times, and makes it possible to supply electric power from vehicles to the vehicles exterior without depending on the charge-and-discharge management system in an emergency.